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Machine learning applications on lunar meteorite minerals:From classification to mechanical properties prediction

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International Journal of Mining Science and Technology 2024年第9期34卷 1283-1292页

作者： Eloy Peña-Asensio Josep M.Trigo-Rodríguez Jordi Sort Jordi ibáñez-Insa Albert Rimola Department of Aerospace Science and Technology Politecnico di MilanoMilano 20156Italy Institut de ciències de l’Espai(IcE-cSIc) Campus UAB08193 Cerdanyola del VallèsSpain Institut d’Estudis Espacials de catalunya(IEEc) Barcelona 08034Spain Departament de Física Universitat Autònoma de BarcelonaCerdanyola del Vallès E-08193Spain Instituciócatalana de Recerca i Estudis Avançats(IcREA) Barcelona E-08010Spain Geosciences Barcelona(GEO3BcN-cSIc) E-08028 BarcelonaSpain Departament de Química Universitat Autònoma de BarcelonaBellaterra 08193Spain

Amid the scarcity of lunar meteorites and the imperative to preserve their scientific value,nondestructive testing methods are *** translates into the application of microscale rock mechanics experiments and scanning electron microscopy for surface composition *** study explores the application of Machine Learning algorithms in predicting the mineralogical and mechanical properties of DHOFAR 1084,JAH 838,and NWA 11444 lunar meteorites based solely on their atomic percentage *** a prior-data fitted network model,we achieved near-perfect classification scores for meteorites,mineral groups,and individual *** regressor models,notably the KNeighbor model,provided an outstanding estimate of the mechanical properties—previously measured by nanoindentation tests—such as hardness,reduced Young’s modulus,and elastic *** considerations on the nature and physical properties of the minerals forming these meteorites,including porosity,crystal orientation,or shock degree,are essential for refining *** findings underscore the potential of Machine Learning in enhancing mineral identification and mechanical property estimation in lunar exploration,which pave the way for new advancements and quick assessments in extraterrestrial mineral mining,processing,and research.

关键词： Meteorites Moon Mineralogy Machine learning Mechanical properties

Myocardial perfusion imaging in patients with a recent, normal exercise test

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World Journal of cardiology 2013年第3期5卷 54-59页

作者： Ann Bovin ib c Klausen Lars J Petersen Department of clinical Physiology Viborg Hospital Department of cardiology Viborg Hospital Department of Nuclear Medicine Aalborg University Hospital

AIM: To investigate the added value of myocardial perfusion scintigraphy imaging (MPI) in consecutive patients with suspected coronary artery disease (cAD) and a recent, normal exercise electrocardiography (EcG). METHODS: This study was a retrospective analysis of consecutive patients referred for MPI during a 2-year period from 2006-2007 at one clinic. All eligible patients were suspected of suffering from cAD, and had performed a satisfactory bicycle exercise test (i.e. , peak heart rate > 85% of the expected, age-predicted maximum) within 6 mo of referral, their exercise EcG was had no signs of ischemia, there was no exercise-limiting angina, and no cardiac events occurred between the exercise test and referral. The patients subsequently underwent a standard 2-d, stress-rest exercise MPI. Ischemia was defined based on visual scoring supported by quantitative segmental analysis (i.e. , sum of stress score > 3). The results of cardiac catheterizationwere analyzed, and clinical follow up was performed by review of electronic medical files. RESULTS: A total of 56 patients fulfilled the eligibility criteria. Most patients had a low or intermediate ATPⅢ pretest risk of cAD (6 patients had a high pre-test risk). The referral exercise test showed a mean Duke score of 5 (range: 2 to 11), which translated to a low postexercise risk in 66% and intermediate risk in 34%. A total of seven patients were reported with ischemia by MPI. Three of these patients had high ATPⅢ pre-test risk scores. Six of these seven patients underwent cardiac catheterization, which showed significant stenosis in one patient with a high pre-test risk of cAD, and indeterminate lesions in three patients (two of whom had high pre-test risk scores). With MPI as a gate keeper for catheterization, no significant, epicardial stenosis was observed in any of the 50 patients (0%, 95% confidence interval 0.0 to 7.1) with low to intermediate pre-test risk of cAD and a negative exercise test. No cardiac events oc

关键词： Single photon emission tomography Ischemic heart disease Myocardial perfusion imaging Pretest risk Post-test risk Added value Exercise electro-cardiography

Efficient Handling of Lock Hand-off in DSM Multiprocessors with Buffering coherence controllers

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Journal of computer Science & Technology 2012年第1期27卷 75-91页

作者： Benjamín Sahelices Agustín de Dios Pablo ibáez Víctor Vials-Yúfera José María Llabería computer Science Department and HiPEAc European Network of Excellence University of Valladolid Valladolid Spain computer Science and Systems Engineering Department I3A Research Institute and HiPEAC European Network of Excellence University of Zaragoza Zaragoza Spain computer Architecture Department and HiPEAc European Network of Excellence Polytechnic University of Catalua Barcelona Spain

Synchronization in parallel programs is a major performance bottleneck in multiprocessor systems. Shared data is protected by locks and a lot of time is spent on the competition arising at the lock hand-off. In order to be serialized, requests to the same cache line can either be bounced （NAcKed） or buffered in the coherence controller. In this paper, we focus mainly on systems whose coherence controllers buffer requests. In a lock hand-off, a burst of requests to the same line arrive at the coherence controller. During lock hand-off only the requests from the winning processor contribute to progress of the computation, since the winning processor is the only one that will advance the work. This key observation leads us to propose a hardware mechanism we call request bypassing, which allows requests from the winning processor to bypass the requests buffered in the coherence controller keeping the lock line. We present an inexpensive implementation of request bypassing that reduces the time spent on all the execution phases of a critical section （acquiring the lock, accessing shared data, and releasing the lock） and which, as a consequence, speeds up the whole parallel computation. This mechanism requires neither compiler or programmer support nor ISA or coherence protocol changes. By simulating a 32-processor system, we show that using request bypassing does not degrade but rather improves performance in three applications with low synchronization rates, while in those having a large amount of synchronization activity （the remaining four）, we see reductions in execution time and in lock stall time ranging from 14% to 39% and from 52% to 7170, respectively. We compare request bypassing with a previously proposed technique called read combining and with a system that bounces requests, observing a significantly lower execution time with the bypassing scheme. Finally, we analyze the sensitivity of our results to some key hardware and software parameters.

关键词： distributed shared memory multiprocessors synchronization buffer coherence controller request bypass

Late complications of pancreas transplant

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World Journal of Transplantation 2020年第12期10卷 404-414页

作者： Javier Maupoey ibáñez Andrea BoscàRobledo Rafael López-Andujar Hepato-Pancreatico-Biliary Surgery and Transplant Unit La Fe University HospitalValencia 46026Spain

To summarize the long-term complications after pancreas transplantation that affect graft function,a literature search was carried out on the long-term complications of pancreatic transplantation,namely,complications from postoperative 3rd mo onwards,in terms of loss of graft function,late infection and vascular complications as *** most relevant reviews and studies were selected to obtain the current evidence on these *** definition of graft failure varies among different studies,so it is difficult to evaluate,a standardized definition is of utmost importance to know the magnitude of the problem in all worldwide *** rejection is the main cause of long-term graft failure,occurring in 10%of *** the 3rd mo of transplantation onwards,the main risk factor for late infections is immunosuppression,and patients have opportunistic infections like:cytomegalovirus,hepatitis B and c viruses,Epstein-Barr virus and varicella-zoster virus;opportunistic bacteria,reactivation of latent infections as tuberculosis or fungal *** preoperative studies and serological tests should be made in all recipients to avoid these infections,adding perioperative prophylactic treatments when *** are uncommon,but one of the main causes of late bleeding,which can be *** treatment should be performed with radiological endovascular approaches or open surgery in case of *** all therapeutic options for the complications mentioned above,transplantectomy is a necessary option in approximately 50%of relaparotomies,especially in lifethreatening *** complications in pancreatic transplantation threatens long-term graft *** exhaustive follow-up as well as a correct immunosuppression protocol are necessary for prevention.

关键词： Pancreas transplantation Pancreas allograft failure Pancreas transplant rejection Pseudoaneurysm Allograft pancreatectomy

Titrimetric Study of the Solubility and Dissociation of Benzoic Acid in Water: Effect of Ionic Strength and Temperature

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American Journal of Analytical chemistry 2015年第5期6卷 429-436页

作者： Sa'ib J. Khouri Department of Basic Sciences American University of Madaba Madaba Jordan

The apparent acid dissociation constant (Kc) of benzoic acid in water has been determined ti-trimetrically under ionic strength values between 0.00 and 0.50 mol·L﹣1 at a range of temperatures between 16°c and 41°c. The thermodynamic dissociation constant (as pKa) of benzoic acid was determined as 4.176 at 25°c. No regular correlation between pKa of benzoic acid and the temperature in the range was used. The values of pKa are inversely proportional to temperatures between 16°c and 30°c. In this range of temperature, the values of thermodynamic quantities () for the dissociation process of benzoic acid in water were calculated by using Van’t Hoff plot. For this case the dissociation was not favoured through entropy and enthalpy changes. The values of pKa are directly proportional to temperatures between 30°c and 41°c.

关键词： Benzoic Acid Ionic Strength Thermodynamic Dissociation constant Salt Effect

Pressurized Liquid Extraction of Pigments from chlamydomonas *** chemical characterization by HPLc–MS/MS

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Journal of Analysis and Testing 2018年第2期2卷 149-157页

作者： Lidia Montero Mahshid Sedghi Yolanda García carlos Almeida carl Safi Nicole Engelen‑Smit Alejandro cifuentes Jose A.Mendiola Elena ibáñez Applied Analytical chemistry University of Duisburg-EssenUniversitaetsstr.545141 EssenGermany Laboratory of Foodomics Bioactivity and Food Analysis DepartmentInstitute of Food Science Research CIAL(CSIC-UAM)Campus de CantoblancoC/Nicolás Cabrera 928049 MadridSpain Spanish Bank of Algae Instituto de Oceanografía y Cambio GlobalFundación Canaria Parque Científico‑TecnológicoUniversidad de Las Palmas de Gran CanariaMuelle de Taliarte s/n35214 Telde(Canary Islands)Spain Wageningen Food and Biobased Research Wageningen University and ResearchPO Box 176700 AA WageningenThe Netherlands

Pressurized liquid extraction using green solvents(ethanol and water)was applied to extract photosynthetic pigments from the microalgae chlamydomonas *** experimental design is employed to determine the effect of the extraction conditions on the extraction yield and the antioxidant capacity of the different extracts determined using 1,1-diphenyl-2-picryl-hydrazyl and TEAc *** the extracts show significant antioxidant activity in all ***,in this work,the carotenoid and chlorophyll composition of the chlamydomonas extracts was analyzed by HPLc–DAD–APcI–MS/MS for the first time,being the main compounds lutein and pheophythin a′.

关键词： Antioxidant capacity chlamydomonas sp. HPLc–DAD–APcI–MS/MS Pigments Pressurized liquid extraction carotenoids

Inflammatory bowel disease: A descriptive study of 716 local chilean patients

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World Journal of Gastroenterology 2016年第22期22卷 5267-5275页

作者： Daniela Simian Daniela Fluxá Lilian Flores Jaime Lubascher Patricio ibánez carolina Figueroa Udo Kronberg Raúl Acuna Mauricio Moreno Rodrigo Quera Academic Research Unit Clinica Las Condes Santiago 7591046 Chile Gastroenterology Departament Clinica Las Condes Santiago 7591046 Chile Inflammatory Bowel Disease Program Gastroenterology Department Clinica Las Condes Santiago 7591046 Chile Inflammatory Bowel Disease Program Colorectal Surgery Department Clinica Las Condes Santiago 7591046 Chile Laboratory of Oncology and Molecular Genetics Colorectal Surgery Clinica Las Condes Santiago 7591046 Chile

AIM: To demographically and clinically characterize inflammatory bowel disease (ibD) from the local registry and update data previously published by our ***: A descriptive study of a cohort based on a registry of patients aged 15 years or older who were diagnosed with ibD and attended the ibD program at clínica Las condes in Santiago, chile. The registry was created in April 2012 and includes patients registered up to October 2015. The information was anonymously downloaded in a monthly report, and the information on patients with more than one visit was updated. The registry includes demographic, clinical and disease characteristics, including the Montreal classification, medical treatment, surgeries and hospitalizations for crisis. Data regarding infection with clostridium difficile (c. difficile) were incorporated in the registry in 2014. Data for patients who received consultations as second opinions and continued treatment at this institution were also ***: The study included 716 patients with ibD: 508 patients (71%) were diagnosed with ulcerative colitis (Uc), 196 patients (27%) were diagnosed with crohn’s disease (cD) and 12 patients (2%) were diagnosed with unclassifiable ibD. The Uc/cD ratio was 2.6/1. The median age was 36 years (range 16-88), and 58% of the patients were female, with a median age at diagnosis of 29 years (range 5-76). In the past 15 years, a sustained increase in the number of patients diagnosed with ibD was observed, where 87% of the patients were diagnosed between the years 2001 and 2015. In the cohort examined in the present study, extensive colitis (50%) and colonic involvement (44%) predominated in the patients with Uc and cD, respectively. In cD patients, non-stricturing/non-penetrating behavior was more frequent (80%), and perianal disease was observed in 28% of the patients. There were significant differences in treatment between Uc and cD, with a higher use of corticosteroids, and immunosupp

关键词： Inflammatory bowel disease crohn’ s disease Ulcerative colitis South America Latin America chile Epidemiology

Shade coffee plantations maintain woody plant diversity and structure in a cloud forest landscape of southern Mexico

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Journal of Forestry Research 2021年第2期32卷 637-648页

作者： Edson AAlvarez-Alvarez R.carlos Almazán-Nunez Fernando González-García Marlene Brito-Millán Alfredo Méndez-Bahena Sergio García-ibáñez Maestría en Recursos Naturales y Ecología Facultad de Ecología MarinaUniversidad Autónoma de Guerrero39390 AcapulcoGuerreroMexico Laboratorio Integral de Fauna Silvestre Facultad de Ciencias Químico-BiológicasUniversidad Autónoma de Guerrero39090 Chilpancingo de los BravoGuerreroMexico Red Biología y conservación de Vertebrados Instituto de EcologíaA.C.CP 91073 XalapaVeracruzMexico University of california Institute for Mexico and the United States(Uc MEXUS) Cuerpo Académico Biodiversidad y Gestión Ambiental SustentableFacultad de Ciencias Químico-BiológicasUniversidad Autónoma de Guerrero39090 Chilpancingo de los BravoGuerreroMexico Laboratorio de Biología de la conservación Facultad de Ciencias Químico-BiológicasUniversidad Autónoma de Guerrero39090 Chilpancingo de los BravoGuerreroMexico Laboratorio de Ecología cuantitativa Facultad de Ecología MarinaUniversidad Autónoma de Guerrero39390 AcapulcoGuerreroMexico

cloud forest ecosystems of the Latin American tropics are highly threatened by changes in land-use such as expanding croplands and livestock pastures that promote shifts in the structure and composition of plant communities in these ***,shade coffee plantations represent a forest management alternative that has been shown to maintain biodiversity in these *** this study,we evaluated changes in the composition,diversity,and structure of Mexican cloud-forest woody species for three land use categories:cattle pastures,shade coffee plantations and advanced succession *** each category,fifteen 0.28-ha plots were established and the composition and diversity of vegetation was *** of species was analyzed using ordination methods,and alpha diversity was compared using Hill ***-seven woody species belonging to 40 families were *** richness and diversity was high in both the advanced successional forest and coffee plantations compared to cattle *** composition and structure was similar between late succession forests and coffee plantations with both land uses also being more structurally complex than cattle *** results show how shade coffee cultivation is a land-use activity that maintains woody plant communities in a manner that aligns with biodiversity conservation.

关键词： Land uses Late succession Plant diversity Shade coffee Vegetation structure

Analgesic Efficacy of Intrathecal Bupivacaine with or without Morphine in Lower Limb Orthopedic Surgery. A comparative Study

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Open Journal of Anesthesiology 2023年第3期13卷 58-74页

作者： Alexis Dun Bo-ib Buunaaim comfort Adubia Fidelis Bayor Sylvanus Kampo Department of Surgery School of Medicine and Health Science University for Development Studies Tamale Ghana Department of Anaesthesia and Intensive care School of Medicine and Health Science University for Development Studies Tamale Ghana Department of Physiology School of Medicine and Dentistry University of Ghana Accra Ghana Department of Anaesthesia and Intensive care School of Medical Sciences C. K. Tedam University of Technology and Applied Sciences Navrongo Ghana

Background: Lower limb orthopaedic surgeries are commonly associated with moderate to severe postoperative pain. Adequate pain relief is essential for patients undergoing such procedures, as uncontrolled pain can lead to delayed recovery, prolonged hospitalization, and increased morbidity. Intrathecal administration of bupivacaine, a long-acting local anesthetic, has been shown to provide effective analgesia after lower limb orthopaedic surgery. However, the duration of analgesia with bupivacaine alone is limited, and the addition of an opioid, such as morphine, can prolong the duration of analgesia. Objective: The objective of this study was to document the comparative effect of adding morphine to intrathecal bupivacaine or only intrathecal bupivacaine for lower limb trauma orthopedic surgeries in terms of onset of action, duration of analgesia, pain severity, and side effects. Methods: This was a comparative longitudinal study design conducted at the Orthopaedic Unit of the Tamale Teaching Hospital. A simple random sampling technique was used to recruit 60 patients. A standard structured questionnaire was also used to collect data on the socio-demographics, and clinical features of patients, drug used,side effects and severity of pain at 24,48 and 72 hrs after surgery. Results: co-administration of intrathecal bupivacaine with morphine produced good and long-lasting postoperative analgesia with a mean time of 1004.25 ± 310.43 minutes, whiles using only bupivacaine produced shorter postoperative analgesia with a mean time of 294.75 ± 195.53 minutes. The p-value p values of p = 0.635 and p = 0.689 respectively. conclusion: The study revealed that co-administration of intrathecal bupivacaine with morphine emerged as a better option for postoperative pain management after lower limb orthopedic surgeries as compared to administering only bupivacaine regarding the duration of analgesia. Milder side effects like pruritus, nausea, and vomiting were seen in group B than in

关键词： Bupivacaine Morphine Pain Analgesia Orthopedic Surgery